feat: iPet → iAs 完整迁移，Rust 版微信 AI 助手

Phase 1 ✅ CLI 框架 + 配置系统
  - clap 子命令: login / listen / send / whoami / usage
  - config.json + env var 替换
  - tracing 日志系统
  - state 持久化（auth/runtime 文件存 + PostgreSQL）

Phase 2 ✅ 微信通道
  - wechat::client — 完整 iLink Bot HTTP API 实现
  - 扫码登录（终端二维码 + 轮询状态）
  - 长轮询 getupdates / 消息收发 / 监听注册

Phase 3 ✅ AI 对话（纯文本 + function calling）
  - LlmProvider trait: DeepSeek + LM Studio 实现
  - SSE 流式解析（text / reasoning / tool_calls delta / usage）
  - Conversation: 消息历史 + chat / chat_with_tools 工具循环

Phase 4 ✅ PostgreSQL 集成
  - app_state（认证 KV 存储）
  - chat_records（消息收发记录）
  - llm_usage（Token 用量统计缓存命中率）
  - user_memories（长期记忆持久化）
  - pending_approvals（审批确认码）
  - scheduled_tasks（定时任务表）

Phase 5 ✅ 一切皆 Skill（工具系统）
  - SkillRegistry: 系统 + 用户 skills 双目录合并
  - SKILL.md 解析器 + 子进程执行器（stdin JSON → stdout）
  - 9 个系统 Skills: datetime / weather / search / email /
    shell / schedule / memos / read_memories / read_summaries
  - ApprovalManager: High 风险技能 → 确认码审批（透明模式）
  - High 风险技能：确认码审批（透明模式）

Phase 6 ✅ 定时任务调度器

上下文管理
  - ChatSession: checkpoint + token budget (28K) + summaries
  - Token 估算器（中英文自适应）
  - 12h 空闲 → trigger_idle_summary（不入会话）
  - Budget 溢出 → trigger_overflow_summary（入会话 + drain 旧消息）
  - Summarizer: LLM 生成自然语言摘要（fallback 简单截断）
  - 长期记忆 / 摘要 通过 read_memories / read_summaries 工具按需读取

工具调用日志 + Token 统计
  - INFO: 工具名 + 参数 + 结果摘要
  - DEBUG: 子进程 exit/stdout/stderr
  - ias usage --since --until --model 查看用量和缓存命中率

src/wechat/types.rs

@@ -0,0 +1,333 @@
+use serde::{Deserialize, Serialize};
+
+// ─── 基础类型 ───
+
+/// 公共请求元数据
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub struct BaseInfo {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub channel_version: Option<String>,
+}
+
+impl BaseInfo {
+    pub fn new() -> Self {
+        Self {
+            channel_version: Some(env!("CARGO_PKG_VERSION").to_string()),
+        }
+    }
+}
+
+// ─── 消息类型 ───
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct TextItem {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub text: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct CDNMedia {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub encrypt_query_param: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub aes_key: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub encrypt_type: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub full_url: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ImageItem {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub media: Option<CDNMedia>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_media: Option<CDNMedia>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub aeskey: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub url: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub mid_size: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_size: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_height: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_width: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub hd_size: Option<i64>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct VoiceItem {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub media: Option<CDNMedia>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub encode_type: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub bits_per_sample: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub sample_rate: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub playtime: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub text: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FileItem {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub media: Option<CDNMedia>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub file_name: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub md5: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub len: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct VideoItem {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub media: Option<CDNMedia>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub video_size: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub play_length: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub video_md5: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_media: Option<CDNMedia>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_size: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_height: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub thumb_width: Option<i32>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RefMessage {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub message_item: Option<Box<MessageItem>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub title: Option<String>,
+}
+
+/// 消息条目（支持 text/image/voice/file/video）
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct MessageItem {
+    #[serde(rename = "type", skip_serializing_if = "Option::is_none")]
+    pub item_type: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub create_time_ms: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub update_time_ms: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub is_completed: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub msg_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub ref_msg: Option<Box<RefMessage>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub text_item: Option<TextItem>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub image_item: Option<ImageItem>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub voice_item: Option<VoiceItem>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub file_item: Option<FileItem>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub video_item: Option<VideoItem>,
+}
+
+impl MessageItem {
+    pub const TYPE_TEXT: i32 = 1;
+    pub const TYPE_IMAGE: i32 = 2;
+    pub const TYPE_VOICE: i32 = 3;
+    pub const TYPE_FILE: i32 = 4;
+    pub const TYPE_VIDEO: i32 = 5;
+
+    pub fn text(text: &str) -> Self {
+        Self {
+            item_type: Some(Self::TYPE_TEXT),
+            text_item: Some(TextItem {
+                text: Some(text.to_string()),
+            }),
+            ..Default::default()
+        }
+    }
+}
+
+impl Default for MessageItem {
+    fn default() -> Self {
+        Self {
+            item_type: None,
+            create_time_ms: None,
+            update_time_ms: None,
+            is_completed: None,
+            msg_id: None,
+            ref_msg: None,
+            text_item: None,
+            image_item: None,
+            voice_item: None,
+            file_item: None,
+            video_item: None,
+        }
+    }
+}
+
+// ─── 微信消息 ───
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct WeixinMessage {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub seq: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub message_id: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub from_user_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub to_user_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub client_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub create_time_ms: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub update_time_ms: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub delete_time_ms: Option<i64>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub session_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub group_id: Option<String>,
+    #[serde(rename = "message_type", skip_serializing_if = "Option::is_none")]
+    pub msg_type: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub message_state: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub item_list: Option<Vec<MessageItem>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub context_token: Option<String>,
+}
+
+impl Default for WeixinMessage {
+    fn default() -> Self {
+        Self {
+            seq: None,
+            message_id: None,
+            from_user_id: None,
+            to_user_id: None,
+            client_id: None,
+            create_time_ms: None,
+            update_time_ms: None,
+            delete_time_ms: None,
+            session_id: None,
+            group_id: None,
+            msg_type: None,
+            message_state: None,
+            item_list: None,
+            context_token: None,
+        }
+    }
+}
+
+impl WeixinMessage {
+    pub const TYPE_NONE: i32 = 0;
+    pub const TYPE_USER: i32 = 1;
+    pub const TYPE_BOT: i32 = 2;
+
+    /// 获取文本内容（如果有纯文本 item）
+    pub fn text_content(&self) -> Option<&str> {
+        self.item_list
+            .as_ref()?
+            .iter()
+            .find(|item| item.item_type == Some(MessageItem::TYPE_TEXT))
+            .and_then(|item| item.text_item.as_ref())
+            .and_then(|t| t.text.as_deref())
+    }
+}
+
+// ─── API 请求/响应 ───
+
+/// 获取二维码响应
+#[derive(Debug, Deserialize)]
+pub struct QRCodeResponse {
+    pub qrcode: String,
+    pub qrcode_img_content: String,
+}
+
+/// 扫码状态响应
+#[derive(Debug, Deserialize)]
+pub struct StatusResponse {
+    pub status: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub bot_token: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub ilink_bot_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub baseurl: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub ilink_user_id: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub redirect_host: Option<String>,
+}
+
+/// GetUpdates 请求
+#[derive(Debug, Serialize)]
+pub struct GetUpdatesReq {
+    pub get_updates_buf: String,
+    pub base_info: BaseInfo,
+}
+
+/// GetUpdates 响应
+#[derive(Debug, Deserialize)]
+pub struct GetUpdatesResp {
+    #[serde(default)]
+    pub ret: i32,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub errcode: Option<i32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub errmsg: Option<String>,
+    #[serde(default)]
+    pub msgs: Vec<WeixinMessage>,
+    #[serde(default)]
+    pub get_updates_buf: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub longpolling_timeout_ms: Option<i64>,
+}
+
+/// SendMessage 请求
+#[derive(Debug, Serialize)]
+pub struct SendMessageReq {
+    pub msg: WeixinMessage,
+}
+
+/// NotifyStart/NotifyStop 响应
+#[derive(Debug, Deserialize)]
+pub struct NotifyResp {
+    #[serde(default)]
+    pub ret: i32,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub errmsg: Option<String>,
+}
+
+/// 登录结果
+#[derive(Debug, Clone)]
+pub struct LoginResult {
+    pub token: String,
+    pub account_id: String,
+    pub base_url: String,
+    pub user_id: String,
+}
+
+/// 收到的消息事件
+#[derive(Debug, Clone)]
+pub struct MessageEvent {
+    pub from_user_id: String,
+    pub text: String,
+    pub context_token: Option<String>,
+    pub message_id: i64,
+}